Serial Monitor read the character enter in Serial monitor

SerialMonitor
//readthecharacterenterinSerialmonitorandprintou
t

charsendChar;

voidsetup(){
Serial.begin(9600);

}

voidloop(){
if(Serial.available()){
sendChar=Serial.read();
Serial.println(sendChar);
}
}

Result

Type“HelloWorld”inmonitor,printout:HelloWorld(wordsbywords)

Toprintinserialmonitorinoneline


charsendChar;

voidsetup(){
Serial.begin(9600);

}

voidloop(){
if(Serial.available()){
sendChar=Serial.read();
Serial.print(sendChar);
}
}

Result

type“helloworld”,printout“helloworld”inoneline

Useserialmonitortocontrol
LED
TypeH,Linserialmonitortocontrolled13inarduinoUnoR3

constintledPin=13;
intincomingByte;


voidsetup(){

Serial.begin(9600);

pinMode(ledPin,OUTPUT);
}

voidloop(){

if(Serial.available()>0){

incomingByte=Serial.read();

if(incomingByte=='H'){
digitalWrite(ledPin,HIGH);
}

if(incomingByte=='L'){
digitalWrite(ledPin,LOW);
}
}
}

Reference:Arduinocc,PhysicalPixel

Transmitdatabetween2arduino


Connection

Arduino1

Arduino2

5V
GND

5V
GND

RX

TX

TX

RX

Send9,8turnon/offledinslavearduino

UploadingthefirmwaretotheArduinobeforeconnectingthe2wireTX
RXbetweenthem.Connectingthese2wireduringuploadingtimemight
ledtotheuploadingproblem.

JustpoweroneArduino

Master

voidsetup(){
Serial.begin(9600);
}

voidloop(){
Serial.println(9);
delay(2000);
Serial.println(8);


delay(2000);
}

Slave

charreceived;
voidsetup(){
Serial.begin(9600);
pinMode(16,OUTPUT);
}

voidloop(){

if(Serial.available()){
received=Serial.read()-48;
Serial.println(received);
if(received==9)
{
digitalWrite(16,HIGH);
}
elseif(received==8)
{
digitalWrite(16,LOW);
}
}
}


Controllingbywords

Master

voidsetup(){
Serial.begin(9600);
}

voidloop(){
Serial.println('H');
delay(2000);
Serial.println('L');
delay(2000);
}

Slave

charreceived;
voidsetup(){
Serial.begin(9600);
pinMode(16,OUTPUT);
}

voidloop(){

if(Serial.available()){
received=Serial.read();


Serial.println(received);
if(received=='H')
{
digitalWrite(16,HIGH);
}

elseif(received=='L')
{
digitalWrite(16,LOW);
}
}
}

NOTE
IfinMaster

received=='High'
received=='LOW'

theninSlave

if(received=='High')
{
digitalWrite(16,HIGH);
}
elseif(received=='Low')
{


digitalWrite(16,LOW);
}

InSerialmonitorofmaster:

2835
2647

InSerialmonitorofslave:

2
8
3
5

2
6
4
7

Soitwon’tworkasthereceiveandsendvariablearechar(meanone
character).

Likealltimes,""isforstring,’’isforchar.

ASCII:‘A’=65;‘0’=48’,…


TosendthewholewordstocontrolLED

Master

voidsetup(){
Serial.begin(9600);
}

voidloop(){

Serial.println("High");
delay(2000);
Serial.println("Low");
delay(2000);
}

Slave

Ifyouchangeto

received=Serial.read();
Serial.println(received);
if(received=="High")
{
digitalWrite(16,HIGH);
}
elseif(received=="Low")
{


digitalWrite(16,LOW);
}

YoustillreveivetheASCIInumber

SoftwareSerial
TypeH,LinmasterArduino,,turnon,offledinslave
Arduino

Connection

Master
5V
GND

Slave
5V
GND

2(RX)

TX

3(TX)

RX

Master

#include<SoftwareSerial.h>
SoftwareSerialArduino(2,3);//RX,TX

charsendChar;
voidsetup(){
Serial.begin(9600);


Arduino.begin(9600);
}

voidloop(){

sendChar=Serial.read();
Serial.print(sendChar);
Arduino.println(sendChar);
delay(1000);
}

Slave

charreceived;
voidsetup(){
Serial.begin(9600);
pinMode(16,OUTPUT);
}

voidloop(){

if(Serial.available()){
received=Serial.read();
Serial.println(received);
if(received=='H')
{
digitalWrite(16,HIGH);


}
elseif(received=='L')
{
digitalWrite(16,LOW);

}
}
}